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=== Pattern indexing ===
[[File:EBSP Indexing and formation.tif|thumb|Formation of Kossel cone which intersects with CCD screen to form EBSP which can be [[Bravais-Miller indices|Bravais-Miller indexed]]|alt=Formation of Kossel cone which intersect with CCD screen to form EBSP which can be Bravais-Miller indexed]]
If the setup geometry is well described, it is possible to relate the bands present in the diffraction pattern to the underlying crystal and [[Orientation (geometry)|crystallographic orientation]] of the material within the electron interaction volume. Each band can be indexed individually by the [[Miller index|Miller indices]] of the diffracting plane which formed it. In most materials, only three bands/planes intersect and are required to describe a unique solution to the crystal orientation (based on their interplanar angles). Most commercial systems use look-up tables with international crystal databases to index. This crystal orientation relates the orientation of each sampled point to a reference crystal orientation.<ref name=":18" /><ref name=":21">{{Citation |last1=El-Dasher |first1=Bassem |title=Application of Electron Backscatter Diffraction to Phase Identification |date=2009 |url=https://digital.library.unt.edu/ark:/67531/metadc1012145/ |work=Electron Backscatter Diffraction in Materials Science |pages=81–95 |editor-last=Schwartz |editor-first=Adam J. |access-date=20 March 2023 |archive-url=https://web.archive.org/web/20230325200543/https://digital.library.unt.edu/ark:/67531/metadc1012145/ |url-status=live |place=Boston, MA |publisher=Springer US |doi=10.1007/978-0-387-88136-2_6 |isbn=978-0-387-88136-2 |archive-date=25 March 2023 |last2=Deal |first2=Andrew |editor2-last=Kumar |editor2-first=Mukul |editor3-last=Adams |editor3-first=Brent L. |editor4-last=Field |editor4-first=David P.|url-access=subscription }}</ref>
Indexing is often the first step in the EBSD process after pattern collection. This allows for the identification of the crystal orientation at the single volume of the sample from where the pattern was collected.<ref>{{Cite web |title=New technique provides detailed views of metals' crystal structure |url=https://news.mit.edu/2016/metals-crystal-structure-0706 |url-status=live |archive-url=https://web.archive.org/web/20230302142459/https://news.mit.edu/2016/metals-crystal-structure-0706 |archive-date=2023-03-02 |website=MIT News {{!}} Massachusetts Institute of Technology|date=6 July 2016 }}</ref><ref name="EBSDSpringer2009">{{cite book |url=https://archive.org/details/electronbackscat00ajsc |title=Electron backscatter diffraction in materials science |date=2009 |publisher=Springer Science+Business Media |isbn=978-0-387-88135-5 |edition=2nd |page=[https://archive.org/details/electronbackscat00ajsc/page/n21 1] |url-access=limited}}</ref> With EBSD software, pattern bands are typically detected via a mathematical routine using a modified [[Hough transform]], in which every pixel in Hough space denotes a unique line/band in the EBSP. The Hough transform enables band detection, which is difficult to locate by computer in the original EBSP. Once the band locations have been detected, it is possible to relate these locations to the underlying crystal orientation, as angles between bands represent angles between lattice planes. Thus, an orientation solution can be determined when the position/angles between three bands are known. In highly symmetric materials, more than three bands are typically used to obtain and verify the orientation measurement.<ref name="EBSDSpringer2009" />
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